Testing means for air compressors



April 23, 1940. D. LOVE 2,198,411

TESTING MEANS FOR A'IR COMPRESSORS Filed Sept. 6, 1958 glvwmoz ,Dfinwni lave ilbtowma Patented Apr. 23, 1940 UNITED STATES PATENT OFFICE TESTING MEANS FOR. AIR COMPRESSORS Dumont Love, St. Augustine, Fla. Application September s, 1938, Serial No. 228,685 4 Claims. (01. 73-51) This invention relates to the class of testingdevices, particularly air compressors of the crosscompound type such as are used on locomotives in air brake equipment for trains or other wheeled vehicles, or wherever such compressors are employed, and pertains particularly to improvements in means for testing certain units of such compressors for air leakage.

In the maintenance of air brake equipmentfor trains, no satisfactory means is at present available for testing the valves and piston packings of cross-compound air compressors while such compressors are maintained in position upon the locomotive, aside from the well-known efficiency orifice test, the present practice being to remove such compressors for examination of the valves and piston packings in the machine shop. This procedure is costly and time-consuming.

The present invention has for its principal object to provide a novel means for testing crosscompound air compressors while the same remain in position upon the locomotive for the purpose of determining whether or not there is leakage past the upper and lower discharge valves, theupper and lower intermediate valves between the high and low pressure air cylinders, the upper and lower inlet valves or the packings or rings for the pis tons of the two compressor cylinders.

Another object of the invention is to provide mechanism whereby tests may be made for leakage of the compressor valves and piston packings, which is easily and quickly applied to the compressor without requiring the making of any structural changes therein, the mechanism being applied to openings which are at the present time a part of the compressor structures.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however, that the invention is not to be confined to any strict conformity with the showing of the drawing but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing, the figure represents the first and second stage air cylinders of a cross-compound air compressor with portions of the high and low pressure steam cylinders connected therewith and showing the mechanism embodying the present invention applied to the first-mentioned cylinders, portions of the air cylinders being in section to show certain of the valves and pistons associated therewith.

Referring now more particularly to the drawing, the principal parts of the first and second stage air cylinders of the compressor will be referred to before describingthe testingdevice and the manner in which it is connected with the cylinders. The cylinder I represents the second stage or high pressure air cylinder while the cylinder 2 represents the first stage or low pressure cylinder. Connected in alined relation with these high and low pressure cylinders are respectively the low pressure steam cylinder 3 and the high pressure steam cylinder 4, the piston in the latter (not shown) being connected by the piston rod 5 with the low pressure cylinder piston 6 which has the usual packing rings 1 encircling it. The low pressure steam cylinder has the piston therein (not shown) connected by the piston rod 8 with the piston 9 of the high pressure or second stage air cylinder I, which latter piston is encircled by the piston rings III.

The numerals II and I2 designate respectively the upper and lower air intake ports for the low pressure air cylinder and the fiow of air through these ports into the cylinder is permitted by inwardly opening valves, the upper one only of which is shown and is indicated by the numeral I3. These upper and lower inlet valves arecovered normally by caps I4, the cap for the lower inlet valve only being shown.

The low and high pressure air cylinders are connected by upper and lower air transfer ports I5 and I6, respectively, the inlet end of each port being controlled by an outwardly opening valve, the upper one of which is shown and indicated by the numeral I'I while each of these valves is covered by a cap, the lower one of which is shown and indicated by the numeral I8. These valves are known as the upper and lower intermediate valves.

At the upper and lower ends of the second stage or high pressure air cylinder are the upper and lower outlet ports I9 and 2|], respectively, each of which leads to a common outlet M which is connected, when the compressor is carried upon a locomotive, with the main air reservoir, and the flow of air through the upper and lower ports I9 and 20 to the outlet 2| is controlled by the upper and lower discharge valves 22 and 23, these valves being accessible from the exterior of the cylinder, like the other valves referred to, by removable caps 24 and 25.

At the ends of the cylinders I and 2 remote I from the steam cylinders, the cylinder heads have threaded openings 26 and 21 which are normally closed by removable plugs not shown.

In carrying out the present invention, the plug normally closing the opening 26 in the lower head of the cylinder I is removed and there is connected with this opening 26 a valve cook 28 which is employed as hereinafter described, in testing for leakage of air from the main reservoir into the high pressure cylinder I past the lower discharge valve 23. This cock has connected with it, after employing it for making the test for leakage of the lower discharge valve 23 and also after testing the lower intermediate discharge valve controlling air flow through the passage IS, a coupling 29 which joints the cook 28 with one side of a T-connection 30, the opposite side of this T having connected therewith an air hose 3!] while the leg or lateral extension of the T is connected by a nipple 32 with a similar T-connection 33.

The cap covering the valve i7 and corresponding with the lower cap I8 is removed and there is secured in its place over the upper intermediate valve I! the coupling 34 to which is attached by means of a union 1' 35, a pet-cock 3t and a cock 31. The cock 31 is connected with a flexible hose 38 which leads to and connects with the T 33.

The plug normally closing the threaded passage 21 in the lower end of the low pressure cylinder 2 is removed and there is connected in the opening 21 one side of a cock'33, the opposite side of which is connected by an air hose 43 with one side of a cock 4! which has its opposite side coupled with the remaining arm of the three-way T 33.

Between the hose 48 and the cock 33 is a T- connection 44, the lateral leg of which has. joined thereto the pipe 45 in which is a cock 46. The opposite end of this pipe 45 in which the cock 46 is located is coupled with one end of a hose 41, the other end of which is connected with an L- coupling 48 as shown.

In order to complete the assembly of the mech-: anism on the compressor, the cap corresponding to cap l4 and covering the upper inlet valve I3 is removed and there is secured in place of this cap a coupling 32 to which is joined by a union L one side of a cook 43, the other side of which may be opened for exhaust to the atmosphere, or, when making a test for leakage of the upper and lower inlet valves, may have the L 58 connected therewith as illustrated in the drawing, and as hereinafter described. 1

In employing the present mechanism for making the several tests, the first test is made to determine if there is leakage of the lower discharge valve 23, the lower intermediate valve at the end of the passage It or of the packing H] of the high pressure cylinder piston 9. The test for leakage of, the lower discharge valve 23 is made preferably before connecting the rest of the apparatus to the cook 23 by means of the coupling 29 and this test is made by first charging the main air reservoir which is connected with the outlet 2! and then stopping the compressor. The air reservoir may be charged from any suitable outside source rather than by the operation or the compressor, if desired, or found necessary. For example, if the compressor is upon a locomotive when the test is being made, the locomotive may not have steam up for the operation of the compressor 3 and 4, in which case it would be necessary to charge the reservoir from some other source as by the operation of another compressor or by carrying air thereto from another compressed air source. The cocks 28, 31, 39 and 43 are open. If the lower final discharge valve 23 or cage leaks, this will be indicated by air escaping from cook 28 as the air will flow back from the air reservoir through the outlet opening 2! and into the cylinder l, and if the upper final discharge valve or cage 22 is leaking, it will be indicated by air escaping from cock 3?, it being understood that the hose 38 will not as yet have been connected with this cock.

In order to test-for air leakage past the upper and lower intermediate valves or cages from the high pressure cylinder to the low pressure cylinder, the hose 3! is connected to the air supply and the connection is made with the cooks 28 and 31, which are open, by means of the hose 3B. The cocks 36 and 4! will be closed. The main air supply cock, not shown, will be opened as well as the cocks 28, 3?, 33 and 43. If the lower M intermediate discharge valves or cages are leaking, this will be indicated by air escaping from cook 39 and if the upper intermediate discharge valves or cages are leaking, this will be indicated by air escaping from cock 43.

- .In order to test for leakage of the packing or rings [0 of the high pressure piston 9, cocks 31 and 4| are closed and cocks 28 and 3B are opened. It the packing ID of the high pressure piston is leaking, air will pass from the side adjacent the cock 28 to the opposite side of the piston and escape by way of the pet-cock 36.

To test for leakage of the low pressure piston packing I, the connection between cock 4! and the cock 39, if not already established, is made by the hose 4|]. Cocks 36 and 46 are closed and all other cocks are opened. If the low pressure piston packing I is leaking, the air will pass from the air supply through the hose 3| and the hose 40 into the lower part of the cylinder 2 and, flowing past the piston S, will escape through cook 43.

To test for leakage of the upper and lower inlet valves or cages, the L 43 is connected with the outlet or discharge side of the cock 43 and the air strainer which is normallly connected with upper and lower inlet ports leading to these valves, the upper port only being shown and indicated by the numeral II, is removed. As is Well known, the air strainer for the air compressor is usually connected with one end of a pipe which has its other end joined to the intermediate portion of a second pipe and this second pipe has each end connected with an inlet port I i, one at the top of the cylinder 2 and the other at the bottom. In detaching the strainer, the same may be disconnected from the single pipe with which it is directly joined or the secondmentioned pipe may have its ends detached from l the cylinder 2 at the upper and lower air inlet ports. After the strainer has been suitably disconnected so that the escape of air past either or both inlet valves may be noted, the upper cock 43 may be opened together with the cock 43 while keeping cock 39 closed and by then opening cock 4| so as to permit air to flow from the source of supply throughthe hose 3! and 4B, and through the hose 4'! to the upper side of the valve I3, the escape of air through the pipe to which the strainer was attached or through the upper port II, will indicate leakage of the valve or cage l3. Also by closingthe cock 43 and opening the cock 39, the escape of air through the lower air inlet port or through the pipe to which the strainer was attached, will indicate leakage of the lower inlet valve or cage. In both of these operations,

the cocks 28 and 31 should be kept open so that air pressure will be applied to the upper and lower intermediate valves to keep the same tightly seated.

From the foregoing, it will be readily apparent that with the mechanism herein described, tests may be easily made upon the valves and piston packings of the air cylinders of an air compressor of the type described without requiring the removal of the compressor from the locomotive, or where such compressor may be in use in a shop or some location other than on a locomotive, the valves may be readily tested without having to move the compressor. 1

What is claimed is: 1 1. A testing apparatus for cross-compound air compressors having adjacent high and low pressure air cylinders, each cylinder containing a piston and having a lower head provided with a removable plug, the high pressure cylinder having upper and lower final discharge valves leading to a discharge port, the low pressure cylinder having upper and lower inlet valves, there being upper and lower intermediate valves between the cylinders and said inlet valves and intermediate valves being accessible from the exterior of the cylinder through removable caps,

said apparatus including a mechanism for testing said discharge valves and said intermediate valves for leakage and testing said pistons for air leakage past the samercomprising an air pipe line connected to the lower head of the high pressure cylinder through the opening occupied by said plug, an air valve connected with the opening normally occupied by the upper intermediate valve cap, a pipe line connected at one end with said first pipe line and having its other end connected with said valve, an air valve interposed in said first pipe line between the high pressure cylinder and the adjacent end of the second pipe, said first-mentioned air valve being coupled with the cap opening by a coupling nipple, a pet-cock connected with said coupling nipple to receive air therethrough from said cap opening and from within the high pressure cylinder when said first valve is closed and air leakage past the high pressure piston occurs on opening the second-mentioned air valve, an air control valve coupled with the opening normally occupied by the upper inlet valve cap, an, air control valve coupled with the opening normally occupied by the lower headplug of the low pressure air cylinder, and an air conducting pipe line connected at one end with said last-mentioned air valve and having its other end connected with the first-mentioned pipe line, said last-mentioned pipe line having an air valve therein.

2. A testing apparatus for cross-compound air compressors having adjacent high and loW pressure air cylinders each cylinder containing a piston and having a lower head provided with a removable plug, the high pressure cylinder having upper and lower final discharge valves leading to a discharge port, the low pressure cylinder having upper and lower inlet valves, there being upper and lower intermediate valves between the cylinders andsaid inlet-valves and intermedi 1 ate valves being accessible from the exterior of the cylinder through removable caps, said apparatus including a mechanism fortesting said discharge valves and said intermediate valves for leakage and testing said pistons for air leakage past the same, comprising an air tight linelconnected to the lower head of the high pressurecylinder through the opening occupied by said plug,

an air valve connected with the opening normal-,

ly occupied by the upper intermediate valve cap, a pipe, line connected at one end with said first pipe line and having its other end connected with said valve, an air valve interposed in said first pipe line between the high pressure cylinder and the adjacent end of the second pipe, said first mentioned air valve being coupled with the cap opening by a coupling nipple, a pet-cock connected with said coupling nipple toreceive air therethrough from said cap opening and from within the high pressure cylinder when saidfirst valve is closed and air leakage past the high pressure piston occurs on opening the second-mentioned air valve, an air control valve coupled with the opening normally occupied by the upper inlet valve cap, an air control valve coupled with the opening normally occupied by the lower head plug of the low pressure air cylinder, an air conducting pipe line connected at one end with said last-mentioned air valve and having its other end connected with the first-mentioned pipe line, said last-mentioned pipe line having an air valve therein, an air pipe line having one end connected with said last-mentioned pipe line between the two last-mentioned air valves and having its other endadapted for connection with the air valve which is coupled in the opening normally occupied by the upper inlet valve cap, and an air control valve in said last-mentioned line.

1 3. A testing apparatus for cross-compound air 1 movable plug, the low pressure cylinder having upper and lower inlet valves, there being upper and lower intermediate valves between the cylinders and each of said upper and lower valves being accessible from the exterior of the compressor through a removable cap, said apparatus including a mechanism for testing saidupper and lower valves for leakage'and testing said pistons forair leakage past the same, comprising an air supply pipe line connected to the lower head of one cylinder through the opening occupied by said removable plug, an air valve connected with each ofthe openings normally occupied by the caps of said valves, pipe lines connected at one end with said first pipe line and eachhaving its other end connected with one of said valves,

and an air valve interposed in said first pipe line between the cylinder and the adjacent end of the second pipe line. 1

4. A testing apparatus for cross-compoundair compressors having adjacent high and low pressure air cylinders, each cylinder containing a piston and having alower head provided with a removable plug, the low pressure cylinder having upper andlower inlet valves, there being upper and lower intermediate valves between the cylinders and each of said upper and lower valves beair valve interposed in said first pipe line between the cylinder and the adjacent end of the second pipe line, and a valve connected between one of the said valves and the adjacent opening and, when opened, discharging to the atmosphere.

DUMONT LOVE. 

